Improvement in ventilating-cowls



UNTTEE STATES PATENT OFFICE. I

JOHN Gr. LAMONT AND GREENLEAF L. SWETT,OF BOSTON, MASSACHUSETTS.

IMPROVEMENT IN VENTlLATlNG-COWLS.

Specification forming part of Letters Patent No. 179,925, dated July 18, 1876; application filed June 26, 1876. A

To all whom it may concern:

Be it known that we, JOHN G. LAMONT and GREENLEAF L. SWETT, both of Boston, in the county of Suffolk and State ot'Massachusctts, have invented an Improvement in Ventilating-Oowls,-of which the following is a specification Thenature of our invention consists in combining with the upper extremity of a ventilating pipe or duct, which hasa protectingshield around it, a series of inclined radial passages, for the purpose of deflecting the wind on the windward side, and to assist in creating a partial vacuum on the lee side.

Figure l is an elevation of our invention. Fig. 2 is a vertical section of the same. Fig. 3 is a cross-section taken on the line wyof Fig. 1.

Let A represent the ventilating pipe or duct. This pipe terminates in a somewhat contracted mouth, as indicated by the inclined sides a a, Fig. 2. Surrounding the top or mouth of this pipe we place the windshield B. (See Figs. 1 and 2.) immediately above the top of the pipe A we place the inclined radial passages, which are formed of the coned platesG and 0, and the vertical divisions D D D D. Above the whole we place the cap H. All of the parts are made securely fast to each other by rods, wires, or strips K K M M, &c., Fig. 2.

By the use of the radial inclined passages,

the wind-shield B with the device 0 G D D D D, by which the radial inclined passages are formed, substantially as described, and for the purpose set forth.

JOHN G. LAMONT.

GREENLEARL. SWETT.

Witnesses:

NATHL. EVANS, WILLIAM EDSON. 

